岩溶区路堤下水平加筋体受力分析方法研究

在岩溶区进行公路修筑时,采用土工织物处理可有效减少岩溶塌陷风险,但目前其计算与设计理论远远落后于工程实践,对其进行研究十分必要。文中首先分析了溶洞上水平加筋体的受力特点,采用太沙基理想土中拱效应理论计算溶洞上方所受荷载,根据各段受力区别,将其划分为临空段、洞端过渡段及锚固段三部分。对加筋体临空段,基于微段分析,导得了洞端水平加筋体拔出位移与加筋体拉力水平分量间的关系;对洞端过渡段,采用库仑摩擦定理,假定摩阻力完全发挥,导得了加筋体拉力损失值计算公式;对锚固段,将其区分为弹性段与塑性段分别求解,并分别考虑有限长与无限长两种情况,导得了其解析解与塑性段长度计算公式,由此可解算锚固段端部拉力与位移间关系曲线。在此基础上,提出曲线交汇法求解整体模型,并将其应用于土工织物拉拔试验及足尺试验的结果分析,计算值与实测值吻合良好。本文方法物理意义明确,简单直观,适合工程应用。

Study on calculating method of horizontally reinforcement beneath embankment constructed in Karst terrain

It is often necessary to implement geosynthetics to reduce risk of sinkhole for road engineering in Karst terrain,while the theory for design and analysis is far behind the engineering practice,so it is of great important to study it.Firstly,the load on the reinforcement was analyzed,and the Terzaghi’s arch theory in ideal soil was introduced to calculate load above cavity.The reinforcement was considered composing of three portions which are free-surface portion,changeover portion and anchored ...